Lymph node size and its association with nodal metastasis in ductal adenocarcinoma of the pancreas

Background

Although lymph node metastasis is a poor prognostic factor in patients with pancreatic ductal adenocarcinoma (PDAC), our understanding of lymph node size in association with PDAC is limited. Increased nodal size in preoperative imaging has been used to detect node metastasis. We evaluated whether lymph node size can be used as a surrogate preoperative marker of lymph node metastasis.

Methods

We assessed nodal size and compared it to the nodal metastatic status of 200 patients with surgically resected PDAC. The size of all lymph nodes and metastatic nodal foci were measured along the long and short axis, and the relationships between nodal size and metastatic status were compared at six cutoff points.

Results

A total of 4,525 lymph nodes were examined, 9.1% of which were metastatic. The mean size of the metastatic nodes (long axis, 6.9±5.0 mm; short axis, 4.3±3.1 mm) was significantly larger than that of the non-metastatic nodes (long axis, 5.0±4.0 mm; short axis, 3.0±2.0 mm; all p<.001). Using a 10 mm cutoff, the sensitivity, specificity, positive predictive value, overall accuracy, and area under curve was 24.8%, 88.0%, 17.1%, 82.3%, and 0.60 for the long axis and 7.0%, 99.0%, 40.3%, 90.6%, and 0.61 for the short axis, respectively.

Conclusions

The metastatic nodes are larger than the non-metastatic nodes in PDAC patients. However, the difference in nodal size was too small to be identified with preoperative imaging. The performance of preoperative radiologic imaging to predict lymph nodal metastasis was not good. Therefore, nodal size cannot be used a surrogate preoperative marker of lymph node metastasis.

The identification of candidate effective combination regimens for pancreatic cancer using the histoculture drug response assay

The prognosis for patients with pancreatic cancer is extremely poor, as they are resistant to first line chemotherapy. The long-term goal of this study was to identify effective combination chemotherapy for pancreatic cancer using pancreatic cancer surgical specimens in the histoculture drug response assay (HDRA) based on three-dimensional culture of tumour fragments, which maintains nature tumour histology in vitro. From 2015 to 2017, the HDRA was performed with tumour specimens from 52 pancreatic cancer patients from Asan Medical Hospital. First, combination drug regimens showed higher drug efficacy and less patient variation than single drugs. Initially, 5-Fluorouracil(5-FU)/Belotecan/Oxaliplatinum and Tegafur/Gimeracil (TS-1)/Oxaliplatinum/Irinotecan were found to be effective. Second, we were able to correlate the efficacy of some drugs with tumour stage. Third, when designing new combination regimens containing 5-FU or gemcitabine, we could identify more effective drug combinations. This is the first study to demonstrate usefulness of the HDRA for pancreatic cancer. Using this technique, we could identify novel candidate combination drug regimens that should be effective in treating pancreatic cancer.

Integrated Analysis of Tissue-Specific Promoter Methylation and Gene Expression Profile in Complex Diseases

This study investigated whether the promoter region of DNA methylation positively or negatively regulates tissue-specific genes (TSGs) and if it correlates with disease pathophysiology. We assessed tissue specificity metrics in five human tissues, using sequencing-based approaches, including 52 whole genome bisulfite sequencing (WGBS), 52 RNA-seq, and 144 chromatin immunoprecipitation sequencing (ChIP-seq) data. A correlation analysis was performed between the gene expression and DNA methylation levels of the TSG promoter region. The TSG enrichment analyses were conducted in the gene-disease association network (DisGeNET). The epigenomic association analyses of CpGs in enriched TSG promoters were performed using 1986 Infinium MethylationEPIC array data. A correlation analysis showed significant associations between the promoter methylation and 449 TSGs' expression. A disease enrichment analysis showed that diabetes- and obesity-related diseases were high-ranked. In an epigenomic association analysis based on obesity, 62 CpGs showed statistical significance. Among them, three obesity-related CpGs were newly identified and replicated with statistical significance in independent data. In particular, a CpG (cg17075888 of PDK4), considered as potential therapeutic targets, were associated with complex diseases, including obesity and type 2 diabetes. The methylation changes in a substantial number of the TSG promoters showed a significant association with metabolic diseases. Collectively, our findings provided strong evidence of the relationship between tissue-specific patterns of epigenetic changes and metabolic diseases.

Rationally designed redirection of natural killer cells anchoring a cytotoxic ligand for pancreatic cancer treatment

The emergence of T-cell engineering with chimeric antigen receptors (CARs) has led to attractive therapeutics; however, autologous CAR-T cells are associated with poor clinical outcomes in solid tumors because of low safety and efficacy. Therefore, the aim of our study was to develop a CAR therapy with enhanced cytotoxicity against solid cancer using allogeneic NK cells. In this study, we engineered "off-the-shelf" NK cells to redirect them towards pancreatic ductal adenocarcinoma (PDAC) by improving their target-specific cytotoxic potential. By integrated bioinformatic and clinicopathological analyses, folate receptor alpha (FRα) and death receptor 4 (DR4) were significantly highly expressed in patient-derived tumor cells. The combined expression of FRα and DR4/5 was associated with inferior clinical outcomes, therefore indicating their use as potential targets for biomolecular treatment. Thus, FRα and DR4 expression pattern can be a strong prognostic factor as promising therapeutic targets for the treatment of PDAC. For effective PDAC treatment, allogeneic CAR-NK cells were reprogrammed to carry an apoptosis-inducing ligand and to redirect them towards FRα and initiate DR4/5-mediated cancer-selective cell death in FRα- and DR4/5-positive tumors. As a result, the redirected cytotoxic ligand-loaded NK cells led to a significantly enhanced tumor-selective apoptosis. Accordingly, use of allogeneic CAR-NK cells that respond to FRα and DR4/5 double-positive cancers might improve clinical outcomes based on personal genome profiles. Thus, therapeutic modalities based on allogeneic NK cells can potentially be used to treat large numbers of patients with optimally selective cytotoxicity.

Estimating Recurrence after Upfront Surgery in Patients with Resectable Pancreatic Ductal Adenocarcinoma by Using Pancreatic CT: Development and Validation of a Risk Score

Background No preoperative model is available for predicting postsurgical prognosis of patients with resectable pancreatic ductal adenocarcinoma (PDAC). Purpose To develop and validate a preoperative risk scoring system using clinical and CT variables to predict recurrence-free survival (RFS) after upfront surgery in patients with resectable PDAC. Materials and Methods In this retrospective study, consecutive patients with resectable PDAC underwent upfront surgery from January 2014 to December 2015 (development set) and from January 2016 to January 2017 (test set). In the development set, multivariable Cox proportional hazard modeling with bootstrapping was used to select clinical and CT variables associated with RFS and to construct a risk scoring system. The discrimination capability of the risk score was assessed by using the Harrell C-index and compared with that of pathologic American Joint Committee on Cancer tumor stage. The risk score was validated in the test set. Results A total of 395 patients were evaluated, including 262 patients (mean age ± standard deviation, 64 years ± 10; 155 men) in the development set and 133 (mean age, 64 years ± 9; 79 men) in the test set. Five independent variables predicted risk of recurrence or death: tumor size (hazard ratio [HR], 1.23; 95% confidence interval [CI]: 1.05, 1.44; P = .009), hypodense tumor in the portal venous phase (HR, 1.66; 95% CI: 1.01, 2.73; P = .04), tumor necrosis (HR, 2.04; 95% CI: 1.38, 3.03; P < .001), peripancreatic tumor infiltration (HR, 1.50; 95% CI: 1.07, 2.11; P = .02), and suspicious metastatic lymph nodes (HR, 1.94; 95% CI: 1.38, 2.72; P < .001). In the test set, the risk score showed good discrimination capability (C-index of 0.68; 95% CI: 0.63, 0.74) and outperformed the pathologic tumor stage (C-index of 0.60; 95% CI: 0.55, 0.66; P = .03). Patients were categorized into favorable, intermediate, and poor prognosis groups with 1-year RFS of 0.87, 0.58, and 0.26, respectively. Conclusion The presented preoperative risk score can predict recurrence-free survival after upfront surgery in patients with resectable pancreatic ductal adenocarcinoma. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Pandharipande and Anderson in this issue.

A Comparative Study of Laparoscopic versus Open Pancreaticoduodenectomy for Ampulla of Vater Carcinoma

Several studies have compared laparoscopic pancreaticoduodenectomy (LPD) and open pancreaticoduodenectomy (OPD) in patients with periampullary carcinoma; however, only a few studies have made such a comparison on patients with ampulla of Vater cancer (AVC). We compared the perioperative and oncologic outcomes between LPD and OPD in patients with AVC using propensity-score-matched analysis. A total of 359 patients underwent PD due to AVC during the study period (76 LPD, 283 OPD). After propensity score matching, the LPD group showed significantly longer operation time than did the OPD group (400.2 vs. 344.6 min, p < 0.001). Nevertheless, the LPD group had fewer painkiller administrations (8.3 vs. 11.1, p < 0.049), fewer Grade II or more severe postoperative complications (15.9% vs. 34.8%, p = 0.012), and shorter postoperative hospital stays (13.7 vs. 17.3 days, p = 0.048), compared with the OPD group. There was no significant difference in recurrence-free outcomes and overall survival between the two groups (p = 0.754 and 0.768, respectively). Compared with OPD, LPD for AVC had comparative oncologic outcomes with less pain, less postoperative morbidity, and shorter hospital stays. LPD may serve as a promising alternative to OPD in patients with AVC.

Propensity score-matched analysis of internal stent vs external stent for pancreatojejunostomy during pancreaticoduodenectomy: Japanese-Korean cooperative project

BACKGROUND

Several studies comparing internal and external stents have been conducted with the aim of reducing pancreatic fistula after PD. There is still no consensus, however, on the appropriate use of pancreatic stents for prevention of pancreatic fistula. This multicenter large cohort study aims to evaluate whether internal or external pancreatic stents are more effective in reduction of clinically relevant pancreatic fistula after pancreaticoduodenectomy (PD).

METHODS

We reviewed 3149 patients (internal stent n = 1,311, external stent n = 1838) who underwent PD at 20 institutions in Japan and Korea between 2007 and 2013. Propensity score matched analysis was used to minimize bias from nonrandomized treatment assignment. The primary endpoint was the incidence of clinically relevant pancreatic fistula. This study was registered on the UMIN Clinical Trials Registry (UMIN000032402).

RESULTS

After propensity score matched analysis, clinically relevant pancreatic fistula occurred in more patients in the external stents group (280 patients, 28.7%) than in patients in the internal stents group (126 patients, 12.9%) (OR 2.713 [95% CI, 2.139-3.455]; P < 0.001). In subset analysis of a high-risk group with soft pancreas and no dilatation of the pancreatic duct, clinically relevant pancreatic fistula occurred in 90 patients (18.8%) in internal stents group and 183 patients (35.4%) in external stents group. External stents were significantly associated with increased risk for clinically relevant pancreatic fistula (OR 2.366 [95% CI, 1.753-3.209]; P < 0.001).

CONCLUSION

Propensity score matched analysis showed that, regarding clinically relevant pancreatic fistula after PD, internal stents are safer than external stents for pancreaticojejunostomy.

Association between Metformin Use and Clinical Outcomes Following Pancreaticoduodenectomy in Patients with Type 2 Diabetes and Pancreatic Ductal Adenocarcinoma

Retrospective studies on the association between metformin and clinical outcomes have mainly been performed on patients with non-resectable pancreatic ductal adenocarcinoma and may have been affected by time-related bias. To avoid this bias, recent studies have used time-varying analysis; however, they have only considered the start date of metformin use and not the stop date. We studied 283 patients with type 2 diabetes and pancreatic ductal adenocarcinoma following pancreaticoduodenectomy, and performed analysis using a Cox model with time-varying covariates, while considering both start and stop dates of metformin use. When start and stop dates were not considered, the metformin group showed significantly better survival. Compared with previous studies, adjusted analysis based on Cox models with time-varying covariates only considering the start date of postoperative metformin use showed no significant differences in survival. However, although adjusted analysis considering both start and stop dates showed no significant difference in recurrence-free survival, the overall survival was significantly better in the metformin group (Hazard ratio (HR), 0.747; 95% confidence interval (CI), 0.562–0.993; p = 0.045). Time-varying analysis incorporating both start and stop dates thus revealed that metformin use is associated with a higher overall survival following pancreaticoduodenectomy in patients with type 2 diabetes and pancreatic ductal adenocarcinoma.

Long-term reversal of diabetes by subcutaneous transplantation of pancreatic islet cells and adipose-derived stem cell sheet using surface-immobilized heparin and engineered collagen scaffold

OBJECTIVE

Esterified collagen (EC) can be functionalized with heparin to enhance islet graft stability. Growth factors secreted by human adipose-derived stem cells (hADSCs) can bind efficiently to EC-heparin (EC-Hep), which enhances revascularization and cell protection. We investigated the therapeutic potential of a combined heparin-esterified collagen-hADSC (HCA)-islet sheet to enhance islet engraftment.

RESEARCH DESIGN AND METHODS

This study was designed to assess the efficiency of using EC-Hep as a scaffold for subcutaneous islet transplantation in diabetic athymic mice. After the hADSC-cocultured islets were seeded in the EC-Hep scaffold, islet function was measured by glucose-stimulated insulin secretion test and growth factors in the culture supernatants were detected by protein array. Islet transplantation was performed in mice, and graft function and survival were monitored by measuring the blood glucose levels. β-Cell mass and vascular densities were assessed by immunohistochemistry.

RESULTS

The EC-Hep composite allowed sustained release of growth factors. Secretion of growth factors and islet functionality in the HCA-islet sheet were significantly increased compared with the control groups of islets alone or combined with native collagen. In vivo, stable long-term glucose control by the graft was achieved after subcutaneous transplantation of HCA-islet sheet due to enhanced capillary network formation around the sheet.

CONCLUSIONS

The findings indicate the potential of the HCA-islet sheet to enhance islet revascularization and engraftment in a hADSC dose-dependent manner, following clinical islet transplantation for the treatment of diabetes mellitus.

Coaxial mussel-inspired biofibers: making of a robust and efficacious depot for cancer drug delivery

Biopolymer-based hydrogels have emerged as promising platforms for drug delivery systems (DDSs) due to their inherent biocompatibility, tunable physical properties and controllable degradability. Yet, drug release in majority of these systems is solely contingent on diffusion of drug molecules through the hydrogel, which often leads to burst release of drugs from these systems. Herein, inspired by the chemistry of mussel adhesive proteins, a new generation of coaxial hydrogel fibers was developed that could simultaneously exert both affinity and diffusion control over the release of chemotherapeutic drugs. Specifically, dopamine-modified alginate hydrogel along with chemotherapeutic drugs (doxorubicin or gemcitabine) was used as the main core component to confer affinity-controlled release, while a methacrylated-alginate hydrogel was used as the shell composition to provide the controlled diffusion barrier. It was shown that our coaxial mussel-inspired biofibers yielded biocompatible hydrogel fibers (as indicated by comprehensive in vitro and in vivo experiments) with favourable properties including controlled swelling, and enhanced mechanical properties, when compared against single fibers made from unmodified alginate. Notably, it was observed that these coaxial fibers were capable of releasing the two drugs in a slower manner, when compared to single fibers made from pure alginate, which was partly attributed to stronger interactions of drugs with dopamine-modified alginate (the core element of coaxial fibers) as observed from zeta-potential measurements. It was further shown that these drug-loaded coaxial fibers had optimal anticancer activity both in vitro and in vivo using various pancreatic cancer cell lines. Most remarkably, drug loaded coaxial fibers, particularly doxorubicin-containing fibers, had higher anticancer effect in vivo compared to systemic injection of equivalent dosage of the drugs. Altogether, these biocompatible and robust hydrogel fibers may be further used as neoadjuvant or adjuvant therapies for controlled delivery of chemotherapeutic drugs locally to the tumor sites.

Comparison of Minimally Invasive Versus Open Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Propensity Score Matching Analysis

Background: Few studies have compared perioperative and oncological outcomes between minimally invasive pancreatoduodenectomy (MIPD) and open pancreatoduodenectomy (OPD) for pancreatic ductal adenocarcinoma (PDAC). Methods: A retrospective review of patients undergoing MIPD and OPD for PDAC from January 2011 to December 2017 was performed. Perioperative, oncological, and survival outcomes were analyzed before and after propensity score matching (PSM). Results: Data from 1048 patients were evaluated (76 MIPD, 972 OPD). After PSM, 73 patients undergoing MIPD were matched with 219 patients undergoing OPD. Operation times were longer for MIPD than OPD (392 vs. 327 min, p < 0.001). Postoperative hospital stays were shorter for MIPD patients than OPD patients (12.4 vs. 14.2 days, p = 0.040). The rate of overall complications and postoperative pancreatic fistula did not differ between the two groups. Adjuvant treatment rates were higher following MIPD (80.8% vs. 59.8%, p = 0.002). With the exception of perineural invasion, no differences were seen between the two groups in pathological outcomes. The median overall survival and disease-free survival rates did not differ between the groups. Conclusions: MIPD showed shorter postoperative hospital stays and comparable perioperative and oncological outcomes to OPD for selected PDAC patients. Future randomized studies will be required to validate these findings.

Prognostic Predictability of American Joint Committee on Cancer 8th Staging System for Perihilar Cholangiocarcinoma: Limited Improvement Compared with the 7th Staging System

Purpose

This study was conducted to evaluate the prognostic values of the 7th and 8th American Joint Committee on Cancer (AJCC) staging systems for patients with resected perihilar cholangiocarcinoma (PHCC).

Materials and Methods

A total of 348 patients who underwent major hepatectomy for PHCC between 2008 and 2015 were identified from a single center. Overall survival (OS) was estimated using the Kaplan-Meier method and compared across stage groups with the log-rank test. The concordance index was used to evaluate the prognostic predictability of the 8th AJCC staging system compared with that of the 7th.

Results

In the 8th edition, the stratification of each group of T classification improved compared to that in the 7th, as the survival rate of T4 decreased (T2, 31.2%; T3, 13.9%; T4, 15.1%; T1-T2, p=0.260; T2-T3, p=0.001; T3-T4, p=0.996). Both editions showed significant survival differences between each N category, except between N1 and N2 (p=0.063) in 7th edition. Differences of point estimates between the 8th and 7th T and N classification and overall stages were +0.028, +0.006, and +0.039, respectively (T, p=0.005; N, p=0.115; overall stage, p=0.005). In multivariable analysis, posthepatectomy liver failure, T category, N category, distant metastasis, histologic differentiation, intraoperative transfusion, and resection margin status were associated with OS.

Conclusion

The prognostic predictability of 8th AJCC staging for PHCC improved slightly, with statistical significance, compared to the 7th edition, but its overall performance is still unsatisfactory.

Prognostic factors predicting survival rate over 10 years of patients with intrahepatic cholangiocarcinoma after hepatic resection

Purpose

Hepatic resection is considered as the optimal treatment for intrahepatic cholangiocarcinoma (IHCC); however, the survival rate after resection is low and the analysis of long-term (≥10 years) survivors is rare. This study aims to analyze the clinicopathological factors affecting the long-term survival of patients with IHCC.

Methods

Between January 2003 and December 2012, a single-institution cohort of 429 patients who underwent hepatic resection for IHCC were reviewed retrospectively. Surgical results, recurrence, and survival rates were investigated, and multivariate analyses were performed to identify prognostic factors.

Results

The overall 1- , 3- , 5- and 10-year survival rates of patients were 76.5%, 44.1%, 33.3%, and 25.1%, respectively. Multivariate analysis showed that the serum CA 19-9 level (≥38 U/mL) (P < 0.001), lymph node (LN) metastasis (P = 0.001), and lymphovascular invasion (LVI) (P = 0.012) were independent factors associated with overall survival. In particular, CA 19-9 level and histologic type were determined to be independent factors affecting survival for more than 10 years.

Conclusion

CA 19-9 (≥38 U/mL), LN metastasis, and LVI were identified as independent risk factors for survival after resection of IHCC. CA 19-9 (<38 U/mL) and histologic type were independent factors predicting survival for more than 10 years.

A Novel Biodegradable Tubular Stent Prevents Pancreaticojejunal Anastomotic Stricture

Stricture of pancreatic-enteric anastomoses is a major late complication of a pancreaticoduodenectomy for the treatment of a periampullary tumor and can lead to exocrine and endocrine insufficiency such as malnutrition and diabetes mellitus. We investigated the safety and efficacy of a biodegradable tubular stent (BTS) for preventing a pancreaticojejunostomy (PJ) anastomotic stricture in both a rat and porcine model. The BTS was manufactured using a terpolymer comprising poly p-dioxanone, trimethylene carbonate, and glycolide. A cohort of 42 rats was randomized into 7 groups of 6 animals each after BTS placement into the duodenum for the biodegradation assay. A total of 12 pigs were randomized equally into a control and BTS placement group. The effectiveness of the BTS was assessed by comparing radiologic images with histologic results. Surgical procedures and/or BTS placements were technically successful in all animals. The median mass losses of the removed BTS samples from the rat duodenum were 2.1, 6.8, 11.2, 19.4, 26.1, and 56.8% at 1, 2, 3, 4, 6, and 8 weeks, respectively. The BTS had completely degraded at 12 weeks in the rats. In the porcine PJ model, the mean luminal diameter and area of the pancreatic duct in the control group was significantly larger than in the BTS group (all p < 0.05). BTS placement thus appears to be safe and effective procedure for the prevention of PJ anastomotic stricture. These devices have the potential to be used as a temporary stent placement to treat pancreatic-enteric anastomoses, but further investigations are required for optimization in human.

Efficacy and Safety of Pembrolizumab in Patients with Refractory Advanced Biliary Tract Cancer: Tumor Proportion Score as a Potential Biomarker for Response

Purpose

The current standard chemotherapy for advanced biliary tract cancer (BTC) has limited benefit, and novel therapies need to be investigated.

Materials and Methods

In this prospective cohort study, programmed death ligand-1 (PD-L1)–positive BTC patients who progressed on first-line gemcitabine plus cisplatin were enrolled. Pembrolizumab 200 mg was administered intravenously every 3 weeks.

Results

Between May 2018 and February 2019, 40 patients were enrolled. Pembrolizumab was given as second-line (47.5%) or ≥ third-line therapy (52.5%). The objective response rate was 10% and 12.5% by Response Evaluation Criteria in Solid Tumor (RECIST) v1.1 and immune- modified RECIST (imRECIST) and median duration of response was 6.3 months. Among patients with progressive disease as best response, one patient (1/20, 5.0%) achieved complete response subsequently. The median progression-free survival (PFS) and overall survival (OS) were 1.5 months (95% confidence interval [CI], 0.0 to 3.0) and 4.3 months (95% CI, 3.5 to 5.1), respectively, and objective response per imRECIST was significantly associated with PFS (p < 0.001) and OS (p=0.001). Tumor proportion score ≥ 50% was significantly associated with higher response rates including the response after pseudoprogression (vs. < 50%; 37.5% vs. 6.5%; p=0.049).

Conclusion

Pembrolizumab showed modest anti-tumor activity in heavily pretreated PD-L1–positive BTC patients. In patients who showed objective response, durable response could be achieved.

Management of isolated recurrence after surgery for pancreatic adenocarcinoma

BACKGROUND

Recurrence of pancreatic cancer after primary pancreatectomy occurs in the vast majority of patients. The role of surgical treatment for recurrent pancreatic cancer is not well established.

METHODS

Patients who underwent primary pancreatectomy with curative intent from 2000 to 2014 at a single large-volume centre were evaluated retrospectively. CT or PET was used to select patients with an isolated recurrence. The clinicopathological features and survival outcomes were compared according to treatment modalities.

RESULTS

Of the 1610 patients with pancreatic cancer who underwent resection, 1346 (83·6 per cent) were diagnosed with recurrent pancreatic cancer. Recurrence was locoregional in 366 patients (27·2 per cent), distant multifocal in 251 (18·6 per cent), distant isolated in 188 (14·0 per cent), locoregional plus distant in 153 (11·4 per cent) and peritoneal seeding in 388 (28·8 per cent). Of the 1346 patients with recurrence, 197 (14·6 per cent) had isolated recurrence; of these, 48 (24·4 per cent of all isolated recurrences; 3·6 per cent of all recurrences) underwent resection. Median survival of the 197 patients after diagnosis of isolated recurrence was 14·7 months; it was longer in patients who underwent surgical resection than among those treated non-surgically (23·5 versus 12·0 months; P = 0·014). Multivariable analysis showed that chemotherapy and resection for recurrence were associated with better prognosis. Median survival after recurrence was longest in the 23 patients with isolated pulmonary recurrence (33·3 months). Survival after recurrence was better in patients who underwent resection of isolated recurrence in the remnant pancreas (median 28·0 versus 12·0 months, P = 0·010) and lung (median 36·5 versus 9·5 months; P = 0·010) than in those who did not undergo resection.

CONCLUSION

Surgical resection may be considered an option for treatment of patients with isolated recurrent pancreatic cancer.

Patterns of prescription opioid use before total hip and knee replacement among US Medicare enrollees

OBJECTIVE

To examine patterns of prescription opioid use before total joint replacement (TJR) and factors associated with continuous use of opioids before TJR.

DESIGN

We conducted an observational cohort study among Medicare enrollees aged ≥65 years who underwent TJR between 2010 and 2014. Preoperative opioid use was defined as having any opioid prescription in the 12-month period before TJR. Patients who had an opioid prescription every month for a 12-month period were defined as continuous users. We examined patients' demographics, pain-related conditions, medication use, other comorbidities, healthcare utilization and their association with use of opioids before TJR.

RESULTS

A total of 473,781 patients underwent TJR:,155,516 THR and 318,265 TKR. Among the total cohort, 60.2% patients had any use of opioids and of those, 12.4% used opioids at least once a month continuously over the 12-month baseline period. Correlates of continuous opioid use included African American race (OR = 2.14, 95% confidence intervals (CI) = 2.01-2.28, compared to White patients), history of drug abuse (OR = 5.18, 95% CI = 3.95-6.79) and back pain (OR = 2.32, 95% CI = 2.24-2.39).

CONCLUSIONS

In this large cohort of patients undergoing TJR, over 60% ever used opioids and 12.4% of them continuously used opioids in the 12-month prior to surgery. Utilization of opioids became more frequent and high-dosed near the surgery. History of drug abuse, back pain, and African American race were strongly associated with continuous use of opioids preoperatively. Further research is needed to determine short-term and long-term risks of preoperative use of opioids in TJR patients and to optimize pre- and post-TJR pain management of patients with arthritis.

Efficacy, Immunogenicity, and Safety of a 9-Valent Human Papillomavirus Vaccine: Subgroup Analysis of Participants From Asian Countries

Background

A 9-valent human papillomavirus-6/11/16/18/31/33/45/52/58 (9vHPV) vaccine extends coverage to 5 next most common oncogenic types (31/33/45/52/58) in cervical cancer versus quadrivalent HPV (qHPV) vaccine. We describe efficacy, immunogenicity, and safety in Asian participants (India, Hong Kong, South Korea, Japan, Taiwan, and Thailand) from 2 international studies: a randomized, double-blinded, qHPV vaccine-controlled efficacy study (young women aged 16–26 years; NCT00543543; Study 001); and an immunogenicity study (girls and boys aged 9–15 years; NCT00943722; Study 002).

Methods

Participants (N = 2519) were vaccinated at day 1 and months 2 and 6. Gynecological samples (Study 001 only) and serum were collected for HPV DNA and antibody assessments, respectively. Injection-site and systemic adverse events (AEs) were monitored. Data were analyzed by country and vaccination group.

Results

9vHPV vaccine prevented HPV-31/33/45/52/58–related persistent infection with 90.4%–100% efficacy across included countries. At month 7, ≥97.9% of participants seroconverted for each HPV type. Injection-site AEs occurred in 77.7%–83.1% and 81.9%–87.5% of qHPV and 9vHPV vaccine recipients in Study 001, respectively, and 62.4%–85.7% of girls/boys in Study 002; most were mild to moderate.

Conclusions

The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Asian participants. Data support 9vHPV vaccination programs in Asia.

Clinical Trials Registration

NCT00543543; NCT00943722.

Propensity score-matching analysis comparing laparoscopic and open pancreaticoduodenectomy in elderly patients

There is little evidence on the safety and benefits of laparoscopic pancreaticoduodenectomy (LPD) in elderly patients; therefore, we evaluated the feasibility and efficacy of this procedure by comparing perioperative and oncological outcomes between LPD and open pancreaticoduodenectomy (OPD) in elderly patients. We retrospectively reviewed the data of 1,693 patients who underwent PD to manage periampullary tumours at a single institution between January 2014 and June 2017. Of these patients, 326 were elderly patients aged ≥70 years, with 56 patients allocated to the LPD group and 270 to the OPD group. One-to-one propensity score matching (56:56) was used to match the baseline characteristics of patients who underwent LPD and OPD. LPD was associated with significantly fewer clinically significant postoperative pancreatic fistulas (7.1% vs. 21.4%), fewer analgesic injections (10 vs. 15.6 times; p = 0.022), and longer operative time (321.8 vs. 268.5 minutes; p = 0.001) than OPD in elderly patients. There were no significant differences in 3-year overall and disease-free survival rates between the LPD and OPD groups. LPD had acceptable perioperative and oncological outcomes compared with OPD in elderly patients. LPD is a reliable treatment option for elderly patients with periampullary tumours.

Robotic versus laparoscopic distal pancreatectomy for left-sided pancreatic tumors: a single surgeon's experience of 228 consecutive cases

BACKGROUND

Laparoscopic distal pancreatectomy (LDP) has gained popularity for the treatment of left-sided pancreatic tumors. Robotic systems represent the most recent advancement in minimally invasive surgical treatment for such tumors. Theoretically, robotic systems are considered to have several advantages over laparoscopic systems. However, there have been few studies comparing both systems in the treatment of distal pancreatectomy. We compared perioperative and oncological outcomes between the two treatment modalities.

METHODS

A retrospective analysis was conducted of all consecutive minimally invasive distal pancreatectomy cases performed by a single surgeon at a high-volume center between January 2015 and December 2017.

RESULTS

The analysis included 228 consecutive patients (LDP, n = 182; Robotic-assisted laparoscopic distal pancreatectomy [R-LDP], n = 46). Operative time was significantly longer in the R-LDP group than in the LDP group (166.4 vs. 140.7 min; p = 0.001). In a subgroup analysis of patients who underwent the spleen-preserving approach, the spleen preservation rate associated with R-LDP was significantly higher than that associated with LDP (96.8% vs. 82.5%; p = 0.02). In another subgroup analysis of patients with pancreatic cancer, there were no significant differences in median overall and disease-free survival between the two groups.

CONCLUSIONS

R-LDP is a safe and feasible approach with perioperative and oncological outcomes comparable to those of LDP. R-LDP offers an added technical advantage that enables the surgeon to perform a complex procedure with good ergonomic comfort.

The efficacy of polyglycolic acid felt reinforcement in preventing postoperative pancreatic fistula after pancreaticojejunostomy in patients with main pancreatic duct less than 3 mm in diameter and soft pancreas undergoing pancreatoduodenectomy (PLANET-PJ trial): study protocol for a multicentre randomized phase III trial in Japan and Korea

BACKGROUND

Partial pancreatoduodenectomy is performed for malignant and benign diseases of the pancreatic head region. The procedure is considered highly difficult and highly invasive. Postoperative pancreatic fistula (POPF) is an important complication because of several consequent complications, including intraabdominal haemorrhage, often increasing hospital stays and surgical mortality. Although many kinds of pancreaticojejunostomy aimed at reducing POPF have been examined to date, the technique has not yet been standardized. We devised a new method using double-coated polyglycolic acid felt after pancreaticojejunostomy. The aim of the PLANET-PJ trial is to evaluate the superiority of polyglycolic acid felt reinforcement in preventing POPF after pancreaticojejunostomy in patients undergoing partial pancreatoduodenectomy to previous anastomosis methods.

METHODS

Patients diagnosed with pancreatic or periampullary lesions in whom it is judged that the main pancreatic duct diameter was 3 mm or less on the left side of the portal vein without pancreatic parenchymal atrophy due to obstructive pancreatitis are considered eligible for inclusion. This study is designed as a multicentre randomized phase III trial in Japan and the Republic of Korea. Eligible patients will be centrally randomized to either group A (polyglycolic acid felt reinforcement) or group B (control). In total, 514 patients will be randomized in 31 high-volume centres in Japan and Republic of Korea. The primary endpoint is the incidence of POPF (International Study Group of Pancreatic Surgery grade B/C).

DISCUSSION

The PLANET-PJ trial evaluates the efficacy of a new method using double-coated polyglycolic acid felt reinforcement for preventing POPF after pancreaticojejunostomy. This new method may reduce POPF.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03331718 . University Hospital Medical Information Network Clinical Trials Registry, UMIN000029647. Registered on 30 November 2017. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000033874.